package com.example.mq.mqserver.datacenter;

import com.example.mq.common.MqException;
import com.example.mq.mqserver.core.Binding;
import com.example.mq.mqserver.core.Exchange;
import com.example.mq.mqserver.core.MSGQueue;
import com.example.mq.mqserver.core.Message;

import java.io.DataOutputStream;
import java.io.IOException;
import java.util.LinkedList;
import java.util.List;

/**
 * 管理所有硬盘上的数据
 * 1. 数据库：交换机，绑定，队列
 * 2. 数据文件：消息
 * 上层逻辑如果现需要操作硬盘，统一通过这个类
 */
public class DiskDataCenter {

    //这个实例用来管理数据库中的数据
    private DataBaseManager dataBaseManager = new DataBaseManager();

    //这个实例用来管理数据文件中的数据
    private MessageFileManager messageFileManager = new MessageFileManager();

    public void init(){
        dataBaseManager.init();
        messageFileManager.init();
    }

    //封装交换机操作
    public void insertExchange(Exchange exchange){
        dataBaseManager.insertExchange(exchange);
    }

    public void deleteExchange(String exchangeName){
        dataBaseManager.deleteExchange(exchangeName);
    }

    public List<Exchange> selectAllExchanges(){
        return dataBaseManager.selectAllExchanges();
    }

    //封装队列操作
    public void insertQueue(MSGQueue queue) throws IOException {
        dataBaseManager.insertQueue(queue);
        // 创建队列的同时，不仅仅是吧队列对象写到数据库中，还需要创建对应的目录和文件
        messageFileManager.createQueueFiles(queue.getName());
    }

    public void deleteQueue(String queueName) throws IOException {
        dataBaseManager.deleteQueue(queueName);
        // 删除队列的同时，不仅仅是把队列从数据库中删除，还需要删除对应的目录和文件
        messageFileManager.destoryQueueFiles(queueName);
    }

    public List<MSGQueue> selectAllQueues(){
        return dataBaseManager.selectAllQueues();
    }

    //封装绑定操作
    public void insertBinding(Binding binding){
        dataBaseManager.insertBinding(binding);
    }

    public void deleteBinding(Binding binding){
        dataBaseManager.deleteBinding(binding);
    }

    public List<Binding> selectAllBindings(){
        return dataBaseManager.selectAllBindings();
    }

    //封装消息操作
    public void sendMessage(MSGQueue queue, Message message) throws IOException, MqException {
        messageFileManager.sendMessage(queue, message);
    }

    public void deleteMessage(MSGQueue queue, Message message) throws IOException, ClassNotFoundException, MqException {
        messageFileManager.deleteMessage(queue, message);
        if(messageFileManager.checkFilesExists(queue.getName())){
            messageFileManager.gc(queue);
        }
    }

    public LinkedList<Message> loadAllMessageFromQueue(String queueName) throws IOException, MqException, ClassNotFoundException {
        return messageFileManager.loadAllMessageFromQueue(queueName);
    }
}
